In recent years, the production of pressurized fluid from geothermal wells has increased substantially as a source of power. The pressurized fluid produced from such geothermal wells either has minerals dissolved therein or entrained therewith, which minerals as the fluid flows from the well tend to be deposited as hard layers in the passages of gate valves and tubular members used in supporting the gate valves on the well head. The depositing of such materials is objectionable, in that, it restricts the transverse cross sections of the passages through which the fluid may flow, and also impairs the operation of the gate valves.
On the normal geothermal well head there will be two oppositedly disposed, axially aligned gate valves that control the flow of pressurized fluid to pipe lines connected thereto. These gate valves are frequently situated in cramped quarters, such as a cellar, and in the past have only been cleanable by killing the well so that they may be removed for maintenance purposes. The killing of a geothermal well is undesirable, in that frequently after the killing the well does not come back to production and the well may even be lost.
A major object of the present invention is to provide an assembly that permits the passages in oppositedly disposed gate valves and tubular members supporting the latter from a geothermal well head to be cleaned of deposited hard minerals, and this operation capable of being carried out without killing the well. Also, the present invention permits the interior of the well head to be sealed, so that a third gate valve that is vertically disposed there above may be removed from the well head for repairs. Repair of the third gate valve is again possible without killing the geothermal well.